pronounced: pell-ar-GO-nee-um species
Pelargonium is derived from the Greek πελαργος (pelargos), the stork, referring to the shape of the seed heads. Geranium is from γερανος (geranos) , the crane, referring to the beak-like fruit. Early botanists lumped the Pelargonium together with a group of fairly similar plants already known as geraniums, and the name has stuck with gardeners ever since.
The first species known to have been cultivated was Pelargonium triste, a native of South Africa. It was thought to have been brought to the Botanical Garden at Leiden before 1600 by ships that stopped at the Cape of Good Hope. In 1631 the English gardener, John Tradescant the Elder, bought seeds from the Paris grower René Morin, and introduced the plant to England. The Pelargonium name was given to the genus by Johannes Burman in 1738.
There are 4 major types of pelargonium:
(i) Ivy leaf pelargoniums, that derive from a single distinctive species Pelargonium peltatum. The leaves look like those of English ivy, and the plant has a wonderful trailing habit that makes it a useful ground cover, for spilling over embankments and the tops of big pots. It also has lovely delicate flowers, often with intricate patterning.
(ii) Zonal pelargoniums, also known as Pelargonium x hortorum, do have quite pretty flowers, but for these plants it’s really all about the foliage. The name comes from the zones or bands of colour in the leaves. They are mainly derived from Pelargonium zonale and Pelargonium peltatum.
(iii) Regal pelargoniums, also known as French Geraniums or Pelargonium x domesticum, develop a shrubby habit in the garden, and grow into a more upright plant. They are mainly derived from Pelargonium cucullatum and Pelargonium grandiflorum. Their glory is their spectacular flowers, which make them ideal for pots, courtyards and garden beds.
(iv) Scented leaf pelargoniums. These are derived from a great number of species, including Pelargonium graveolens.
Pelargonium leaves are usually alternate, and palmately lobed or pinnate, often on long stalks, and sometimes with light or dark patterns. The erect stems bear 5-petaled flowers in umbel-like clusters called pseudoumbels. The flowers have been bred to a variety of shapes ranging from star-shaped to infundibuliform, and colours include white, pink, red, orange-red, fuchsia to deep purple.
Pelargoniums produce flower buds for most of year. If the old flower stems are pinched out as they finish, the plants will look after themselves.
Pelagoniums act as food plants for a number of Lepidoptera caterpillars, including:
• the Cotton Cutworm Spodoptera litura;
• the Cotton Bollworm Helicoverpa armigera;
• the Black-bodied Browntail Moth Euproctis melanosoma;
• the Geranium Plume Moth Sphenarches anisodactylus;
• the Green Looper Chrysodeixis eriosoma; and
• the moth Orgyia australis.
Other than being grown for their beauty, some species of pelargonium are important in the perfume industry. Although there are scented species with the scents of citrus, mint, or various fruits, the varieties with rose scents are the most commercially important, and are often used to supplement or adulterate the more expensive rose oils.
